Jackson 648 Tube Tester Manual [EXCLUSIVE]

I have never had a Jackson 648 work incorrectly. The Jackson series was the obvious choice for me as my primary tube tester. I have never had an electrostatic discharge problem with any of the 648 series. The Jackson series behaves well with all types of tubes. It is well versed in audio. In fact, it probably has the best audio load, harmonic distortion and sensitivity on the market.

The Jackson series is an excellent customer-service instrument. I have never encountered any technical difficulties. In fact, this unit has been around for many years. I have simply enjoyed using it for many years. The Jackson series is also recommended by many tube sellers.

The Jackson series has a wide range of output states, from the 0.5 mA minimum test current to the high current range of 100 mA or more. It is a great unit for me because I can test a wide variety of tubes with a minimum of costs and effort.

The Jackson series uses internal standard tube voltages of 1.5 volts in the middle of the range. These are usually in the 500 to 2,000 volt range. The Jackson series uses the 647 metric system and is capable of testing a wide range of types. It can test all types of bakelites, all types of 6B7s, many types of EL34s, and many types of KT88s.

The Jackson series has an excellent oscilloscope input with up to 20 MHz of bandwidth. It has analog to digital input conversion. It is a quality output. It has an output ranging from 2mV to 40 volts.

The Jackson series features some of the most intuitive controls I have seen. It is an HV meter, an oscilloscope, a dual range voltmeter, a sweep meter, a digital voltmeter, a bright meter, and a line scan oscilloscope. It can measure in the 10 microvolt to 10 milliwatt range.

Cons: Although the 648 is a very popular tube tester, it is rather large, heavy, and expensive. In comparison to the rather small, light, and inexpensive Hickok 539A tube tester, the Jackson 648 is a very expensive and heavy to hold. The Jackson 648-series is also fairly large and bulky. The Jackson 648-series does come with a 30-year warranty, but I've had to replace one of the 648-series at least once in that time. It can be quite hard to find a full set of spare parts.

Conclusions: Although the Hickok 539A tube tester is a very popular and popular tube tester in Europe, it doesn't seem to be well-known in the USA. In comparison to the Jackson 648, the Hickok 539A is a fairly cheap ($200.00 retail) and a lot lighter. It also has a smaller footprint and it's a lot smaller, lighter, and easier to hold. Both the Jackson 648 and the Hickok 539A use a simple single-channel design. The Hickok 539A is available in a 60-pin version (the Jackson 648-series is not). The Jackson 648-series also has more features than the Hickok 539A. The Jackson 648-series can be a bit more expensive than the Hickok 539A. The Jackson 648-series is also larger and heavier than the Hickok 539A. For most tube testers, though, the Jackson 648-series is a great choice. 827ec27edc